<div>
   <button type="button" class="btn btn-primary" ng-click="alert1()">弹出框1</button>
   <button type="button" class="btn btn-primary" ng-click="alert2()">弹出框2</button>
   <button type="button" class="btn btn-primary" ng-click="alert3()">弹出框3</button>
   <button type="button" class="btn btn-primary" ng-click="alert4()">弹出框4</button>
</div>